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Web3.js

Web3.js​

Web3.js was established in 2014, making it the oldest web3 library. With extensive documentation, an active community and modular design, Web3.js is powerful and easy-to-use. It has support for Celo features via plugins since version 4.13.1.

The Web3.js docs have excellent examples of how to use it in your project.

With Celo​

For basic use web3 works out of the box.

For Celo' specific features like Fee Abstraction transcations you need to install @celo/web3-plugin-transaction-types as well as web3@4.13.1 or higher. This also adds utils like getCoreContractAddress for fetching core contract address from onchain registry.

// see web3 docs for more info on setup

import { Web3 } from "web3";
import { CeloTransactionTypesPlugin } from "@celo/web3-plugin-transaction-types";

const web3 = new Web3("http://127.0.0.1:8545");
web3.registerPlugin(new CeloTransactionTypesPlugin());

// Now `web3.celo` is available and `celo.eth` is celo-aware

const cEUR = await web3.celo.getCoreContractAddress("StableTokenEUR");
const txData = {
  from: "0x123...",
  to: "0x456...",
  value: 123n,
  feeCurrency: cEUR, // optional
};
await web3.celo.populateTransaction(txData);
const tx = await web3.eth.sendTransaction(txData);

Gas Price​

When paying for transaction with an alternate feeCurrency token it is important to know the price of gas denominated in that token. You can use web3.celo.populateTransaction to make sure maxPriorityFeePerGas, maxFeePerGas, and gas are filled properly.

await web3.celo.populateTransaction(txData);

More examples in the github repository readme.